A package bag provided with a spout has been widely used as, for example, a package bag which accommodates contents for refill, in order to easily discharge the contents therefrom.
Patent Document 1 discloses a bag having a reinforcement mechanism constituted by two linear deformations which are formed by performing deformation processing on a film, in order to prevent bending of a spout portion.
Patent Document 2 discloses a package bag provided with a reinforcement layer formed on a base material having a flow passage introduction portion of a spout, a flow passage of the spout, and the like, by applying curable resin to the base material, or by adhering a reinforcement piece to the base material.
Patent Document 3 discloses a pouch container having: a planar protruding processed portion which is formed in a region where an opening cutting line is disposed; and a protruding processed portion which protrudes outward from a wall of the pouch, such as a first linear protruding processed portion which is formed in a center line direction, second linear protruding processed portions which are formed in both sides of the first protruding processed portion along the first protruding processed portion, and a third linear protruding processed portion which is formed in a direction intersecting the center line.